Apparatus for mixing a solid particulate material with a liquid and for periodically dispensing the mixture



July 30, 1968 D. W M CULLOCH APPARATUS FOR MIXING A SOLID PARTICULATE MATERIAL WITH A LIQUID AND FOR PERIODICALLY DISPENSING THE MIXTURE Filed Feb. 23. 1967 INVENTOR. 0on5 M4MC04406H United States Patent C APPARATUS FOR MIXING A SOLID PARTICULATE MATERIAL WITH A LIQUID AND FOR PERIODI- CALLY DISPENSING THE MIXTURE Doyle W. McCulloch, 630 Walnut Circle E., Garland, Tex. 75040 Filed Feb. 23, 1967, Ser. No. 618,066 14 Claims. (Cl. 222-56) ABSTRACT OF THE DISCLOSURE Apparatus for intimately mixing a solid particulate material with a liquid and periodically dispensing the mixture in alternating sequence with dispensation of the unmixed liquid. The apparatus includes a hopper for the particulate material and means for discharging this ma terial into a mixing chamber disposed below the hopper which contains the liquid. The liquid is introduced to the chamber through the open top thereof by a weir or overflow effect from a surrounding space which is defined by the chamber and a surrounding confining member. Means is provided for automatically, periodically, and in alternating sequence, withdrawing the mixture from the chamber, and the liquid from the space between the chamber and the confining member.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to apparatus for intimately mixing particulate material with a liquid, and for periodically dispensing the mixture. More specifically, but not by way of limitation, the present invention relates to an apparatus for intimately mixing particulate soap with water preparatory to dispensing the mixture in a car washing system or the like, with the dispensation of the soapwater mixture being alternated with the dispensation of relatively pure water.

Descripti n of the prior art Automatic car washing systems have come into widespread use in this country in recent years and operate upon a variety of principles. Generally, however, such systems broadly entail a washing cycle and a rinsing cycle during the vehicle washing operation. In the washing cycle, water mixed with any one of several types of chemicals is directed against the vehicle for the purpose of loosening dirt, grease and other undesirable deleterious materials from the external surface of the vehicle. Following this step of the process, a rinsing step is employed to remove from the vehicle the mixture of water and chemicals used in the washing step and thus prevent staining or the deposit of residual materials which may be chemically harmful to the paint on the vehicle.

In systems of the type in previous use for accomplishing the automatic washing of vehicles, it has previously been diflicult to obtain the proper degree of entrainment of soap or additive particles in the water for use in the washing step of the process. At times, the soap is incompletely dissolved and does not lather or foam properly when it is directed against the vehicle. In other instances, though a relatively good admixture of the water and soap or detergent is obtained, such thorough mixing is attained only at the expense of an uneconomic consumption of the additives. Another problem which has been characteristic of many types of automatic car washing systems heretofore in use is that water used in the rinse cycle of the process continues to carry, or to be mixed with, a certain amount of soap, so that the rinsing step is inefficient, and an excessive amount of water is required in this step in order to remove to a satisfactory degree, the soap which may remain on the vehicle from the washing step of the process.

Summary of the invention Broadly described, the present invention comprises a housing for an additive material, such as granulated or powdered soap, and a chamber positioned below the additive housing for receiving additive therefrom. A liquid confining member is positioned adjacent the chamber and is dimensioned to confine a liquid to a position adjacent at least a portion of the chamber and to direct liquid into the chamber from the top thereof. Means is provided for dispensing the additive material into the chamber from the housing, preferably with the aid of gravity.

Additionally, the apparatus of the invention further includes means for directing a liquid between the confining member and the chamber. Control means is connected to the liquid directing means and includes liquid level sensing elements disposed in the chamber and also between the confining member and the chamber for automatically controlling, within predetermined limits, the level of liquid between the chamber and the confining member, and also in the chamber. Means is provided for periodically withdrawing mixed additive and liquid from the interior of the chamber, and finally, means is provided for periodically withdrawing liquid from between the confining member and the chamber.

In a specific exemplary embodiment of the invention, a soap powder-containing hopper is positioned over a mixing chamber which is preferably laterally surrounded by an encircling rigid confining member so that wash water can be confined between the confining member and the mixing chamber. The confining member is made to extend to a greater height than the mixing chamber which is open at its top, so that a weir effect is obtained by the movement of water into the mixing chamber by flow over its upper edge.

A conduit containing appropriate valving is connected to the lower end of the mixing chamber for removing the soapy water mixture therefrom and conveying it to a pump. Conduit and valving means is also provided in communication with the space between the confining member and the mixing chamber so that water can be either introduced to the zone, or can be removed therefrom by the same pump to which is connected the conduit used to remove soapy water from the mixing chamber.

Suitable float switches are provided in both the mixing chamber and in the space between the mixing chamber and the confining member so that the water levels in both zones can be regulated within predetermined limits by water supplied through the conduit which communicates with the space between the confining member and the mixing chamber.

An appropriate programming device is connected to the described valve and pump elements of the system of the invention so that during one portion of the washing operation using the described apparatus, the soapwater mixture is withdrawn from the bottom of the mixing chamber and is distributed through the pump to a point of application of the soapy water. After the programmer has timed out this first phase of the washing operation, fresh, pure water is withdrawn from the space between the confining member and the mixing chamber and is directed through the pump to the same ultimate outlet, and provides rinse water to consummate the rinsing cycle of the operation.

The novel construction of the system as thus described achieves the objects of more perfectly mixing the soap and water prior to its application to a vehicle or other object to be washed, and of providing pure, clean rinse water which has not been contaminated by soap at such time as the rinsing cycle is commenced.

In addition to these objects, an additional, important object of the invention is to provide a mechanically sin.- ple, ruggedly constructed apparatus for mixing a particulate material with a liquid in intimate admixture, and for periodically dispensing this mixture in alternating sequence with dispensation of the liquid without the additive incorporated therein.

An additional object of the invention is to provide a more positive and mechanically reliable device for feeding soap particles to a mixing zone in an automatic car washing system. An additional object of the present invention is to provide an automatically programmed, highly efiicient soap mixing apparatus for utilization in automatic car wash systems.

In addition to the foregoing described objects and advantages, additional objects and advantages will become apparent as the following detailed description of the invention is read in conjunction with the accompanying drawings which illustrate the invention.

Description of the drawings FIGURE 1 is a view in elevation of the mixing and dispensing apparatus of the invention.

FIGURE 2 is a vertical sectional view taken through the structure depicted in FIGURE 1, except for certain conventional elements which are illustrated in elevation.

FIGURE 3 is a detail view depicting the apparatus employed to dispense solid particulate soap from a hopper utilized to contain this material in the system of the invention.

FIGURE 4 is a schematic wiring diagram depicting electrical circuitry which can be utilized in a preferred embodiment of the invention.

Description of the preferred embodiment In the drawings, systems or broad combinations comprising a plurality of subcombinations are designated by reference numerals having lead lines with arrowheads. Subcombinations are designated by reference numerals which are underlined, and individual elements of structure are designated by plain reference numerals and lead lines.

Referring now to the drawings, and initially to FIG- URE 1, the mixing and dispensing apparatus of the invention comprises a generally vertically extending framework which includes a plurality of upright stanchions 12 and a horizontal base plate 13. The upright stanchions 12 are horizontally spaced from each other and support a soap particle hopper 14 and a liquid confining member 16. It will be perceived that the soap particle hopper 14 is disposed directly above the liquid confining member 16, and that in the embodiment of the invention illustrated, both the hopper and the liquid confining member 16 are of inverted conical configuration. The lower end of the soap particle hopper 16 is secured to a feeder housing 18 which includes a bottom wall 20 having an aperture 22 disposed on one side thereof, and a top wall 24 having an aperture 26 formed therethrough on the opposite side of the feeder housing from the aperture 22. A generally cylindrical side wall 28 completes the closure of the feeder housing 18.

Supported on the lower end of a drive shaft 3'!) and within the feeder housing 18 is a feeder paddle which includes a plurality of vanes 32 extending radially outwardly from the drive shaft 30. A cross member 34 extends diametrically across the relatively large diameter top portion of the soap particle hopper 14 and supports a motor 36 which is drivingly connected to the drive shaft 30. The vanes 32 are driven in rotation in the feeder housing 18 by the motor 36 through the connection afforded by the drive shaft 30.

As best illustrated in FIGURE 2 of the drawings, the liquid confining member 16 is also geometrically configured as an inverted cone, and is provided with a vertically extending peripheral skirt 40 at the upper end thereof which is secured to the stanchions 12 and which, in conjunction with one of the stanchions, supports a switch box 42. At its lower end, the liquid confining member 16 is connected to a suitable fitting 44 which places the lower end of the conically shaped confining member 16 in communication with a pipe 46. The fitting 44 is constructed to permit a pipe 48 to be extended therethrough in sealing engagement therewith and connected to the lower end of a conically shaped mixing chamber 50 disposed within the confining member 16. Thus, a fluent material contained within the mixing chamber 50 may be withdrawn therefrom through the pipe 48.

Extending from the switch housing 42 are a pair of float fingers 52 and 54. The float fingers 52 and 54 carry at their lower ends, a pair of float elements '56 and 58, respectively, which are positioned by the configuration and length of these fingers within the space defined between the liquid confining member 16 and the mixing chamber 50, and in the interior of the mixing chamber 59, respectively. The float fingers 52 and 54 are pivotally mounted in the switch box 42 so that the floats may move freely up and down in response to variations in the levels of liquids within the respective spaces in which they are located.

Before proceeding further with the identification of the structure included in the present invention, it should be pointed out that the geometric configuration and size of the liquid confining member 16 and the mixing chamber 50 are of some importance to the optimum functioning of the present invention. Thus, although for the invention to attain operativeness, it is only necessary that the liquid confining member 16 define an open space with a second element which forms an enclosure which will hold the ingredients to be mixed, either a conical or pyramidal configuration is preferred for the liquid confining member and the mixing chamber. Further than this, whatever geometric configuration may be adopted for these two structural elements it is highly desirable that the liquid confining member 16 form with the mixing chamber 50, a space which entirely surrounds or encircles the mixing chamber. The purpose of such encirclement is to permit liquid to flow over the open top edge of the mixing chamber from all directions or all sides (during operation of the device) rather than from merely one side. The advantage of this type of entering flow from all directions will be hereinafter discussed in greater detail. Finally, it is desirable, though not critical, that the volume of the space enclosed by the mixing chamber 50 be substantially equal to the volume of the space which is defined between the mixing chamber and the liquid confining member 16.

A pump 60, which is preferably a turbine pump for reasons hereinafter explained, is connected to a discharge pipe 62 and to an intake pipe 64 is connected to the pipe 48 through a three way valve 66. The three way valve 66 is also connected to a suitable pipe or conduit 68 which is connected through a T fitting 70 to the pipe 46. The T fitting 70 is also connected to a conduit 72 connected to an electrically operated solenoid valve 74 which functions in a manner hereinafter described. A conduit 76 connects the electrically operated solenoid valve 74 to a source of the washing liquid to be used by the apparatus, such source being any device suitable for constantly supplying an amount of such liquid to the conduit 72 through the valves 74 at a rate suflicient to supply this liquid faster than the turbine pump 69 can discharge the same liquid through the discharge pipe 62. The reason for this high supply capacity will become apparent as the description of the invention proceeds.

The electrical circuitry used in conjunction with the structure depicted in FIGURES l and 2 and hereinbefore described is shown in FIGURE 4 of the drawings. The circuitry includes a suitable source of electric power 80 which is connected through a main switch 81 to an electrical programmer. The function of the programmer 82 is simply that of developing, in a timed sequence, electrical pulses or signals sufficient to operate the solenoid valves 66 and 74, the turbine pump 60' and the motor 36. Devices of this type are well known in the art.

As depicted in FIGURE 4, the pump 60, motor 36 and solenoid valve 66 are connected in series with the programmer 82 and in parallel with each other. Also connected in parallel with the pump 60, motor 36 and programmer 82 is the coil of the solenoid valve 74. Two switches 56s and 58s are connected in series with the solenoid valve 74 but in parallel with each other. These switches are located in the switch box 42 and are opened and closed by movement of the floats 56 and 58 as hereinafter explained. A safety switch 86 is connected in series with the pump 60.

OPERATION As has been previously mentioned herein, one of the most useful applications of the present invention is for providing the wash and rinse liquids used in an automatic car washing system. In view of the importance of this use of the apparatus of the invention, and its effectiveness when employed in this manner, the operation of the invention will be described in this context. Let it be assumed at the outset of the operation, that an automobile has moved into a building or enclosure containing an automatic car washing system which incorporates the present invention. As is does so, the main switch 81 in the illustrated electrical circuitry of this system is closed. The closure of the main switch 81 may be effected by deposition of a coin in a coin receptacle, by a light beam interrupted by the automobile as it moves into position, or in any other suitable manner. When the switch 81 is closed, electrical power is applied to the programmer 82. At this time, which corresponds to the start of the washing cycle, let it be assumed that water disposed in the space between the confining member 16 and the mixing chamber 50 is at the level shown in FIGURE 2, and water is also at the level indicated in FIGURE 2 within the mixing chamber 50. With these water levels in the described zones, the float switches 56s and 58s are both open due to the elevation of the float elements 56 and 58. In the illustrated position of the float elements 565 and 58, and with the float switches 56s and 58s open, solenoid valve 74 is closed so that no water is directed from the conduit 76 through the conduit 72 and fitting 70 into the space surrounding the mixing chamber 50.

At this time, i.e., the start of the Wash cycle, the programmer 82 permits the circuit to be completed through the three way solenoid valve 66 to shift this valve so that the pipe 48 is placed in communication with the intake pipe '64 to the turbine pump 60. The pipe 68, on the other hand, is isolated from the turbine pump in this initial status of the three way valve 66. The motor 36 is energized and the turbine pump 60 is actuated by the programmer 82 at the commencement of the washing cycle. The energization of the motor 36 rotates the drive shaft 30 and causes the radial blades or vanes 32 to be rotated in the feeder housing 18. As these vanes 32 are rotated, soap which gravitates through the opening 26 is picked up by the vanes and is moved circumferentially in the feeder housing 18 until it reaches the opening 22 in the lower wall thereof. From the opening 22, the soap falls into the open upper end of the mixing chamber 50. The operation of the turbine pump 60 functions to withdraw the wate'r-soap mixture from inside the mixing chamber 50 through the pipe 48 and the three way valve 66, and to discharge this mixture through the discharge pipe 62. This discharge pipe 62 can be suitably connected to dispensing nozzles or heads not shown which direct the soapy water mixture against the automobile in conformity with conventional practice in automatic car washing systems.

As the liquid level drops in the mixing chamber 50, the float 58 also drops and the float switch 58s is closed. Closure of the float switch 58s energizes the electrical solenoid valve 74 to place the conduit 76 in communication with the conduit 72. Thus, makeup water from the water supply (not shown) is introduced via the pipe 46 and fitting 44 to the space between the confining member 16 and the mixing chamber 50. The water continues to enter this space until it reaches the free upper edge of the mixing chamber 50 and flows thereover. A weir effect is thus developed where water flows into the open upper end of the mixing chamber 50 from all sides thereof. The flow of water into the mixing chamber 50 is continued so as to tend to restore the level of the liquid in the mixing chamber to a height sufiicient to maintain the float 58 at the position shown in FIGURE 2. The cascading of the water over the free upper edge of the mixing chamber 50 performs a mixing function as the water comes down upon the soap powder which tends, to some extent, to float on the top of the water in the mixing chamber before becoming intimately mixed therewith. Further, since the space between the confining member 16 and the mixing chamber 50 completely surrounds the mixing chamber, the water flowing over the top of the mixing chamber enters the' interior thereof from all directions, and thus a turbulence is created in the center of the mixing chamber, and there is no tendency for the soap particles to be washed or moved to one quiescent side of the mixing chamber to the exclusion of other sides thereof. During the entire wash cycle, that is, during the entire time that the turbine pump 60 is withdrawing water from the lower end of the mixing chamber 50, the water level in the zone or space between the confining member 16 and the mixing chamber will remain even with the upper edge of the mixing chamber 50 since water must be constantly supplied from this zone to the interior of the mixing chamber in order to replace the liquid which is being withdrawn from the mixing chamber by the turbine pump.

It should be noted that the turbine pump 60 is preferred for use in the present invention since it accomplishes a thorough mixing of the water and entrained soap due to its shearing action, and also is not subject to cavitation as are centrifugal pumps when used in the described apparatus. Centrifugal pumps may, however, be used without complete loss of operativeness of the invention.

The washing cycle involving withdrawal of the soapwater mixture from the interior of the mixing chamber 50 by the turbine pump 60 continues for a period of time determined by the programmer 82. At the end of this time, the programmer 82 opens the circuit to the motor 36 so that this motor is stopped and soap is no longer dispensed from the hopper 14 to the mixing chamber 50. At this time, the programmer 82 also shifts the three way solenoid valve '66 so that the valve places the pipe 68 in communication with the turbine pump 60. The turbine pump 60 thus commences to draw fresh water, unmixed with soap, from the space or zone defined bet-ween the confining member 16 and the mixing chamber 50.

As the water level in this zone drops, the float element 56 also moves downwardly to close the switch 56s associated therewith. The switch 56s should be a type which has a delay element built into the switch so that the water level may drop a short distance in the space between the confining member 16 and mixing chamber 50 before the switch will close, thereby closing the electrical circuit to the solenoid valve 74 and permitting a supply of makeup water to be introduced from the conduit 76. As has been previously explained, the rate at which water is supplied through this conduit is greater than that at which it is withdrawn from the system by the turbine pump 60 so that the water level in the space between the confining member 16 and the mixing chamber 50 will be restored.

The programmer 82 will continue to time the rinsing cycle until a sufficient amount of clean rinse water has been discharged by the turbine pump 60 to the dispensing heads and used to thoroughly rinse the automobile or other object to which the clean water is to be applied. At this time, the programmer 82 will time out, thus interrupting the circuit to the pump and stopping its operation. The washing cycle is then completed. The main switch 81 will, of course, be employed in conjunction with some type of relay or other device which will permit it to remain closed during the washing and rinsing cycles hereinbefore described, and to be opened at the end of this period.

A final element of the circuitry which is depicted in FIGURE 4 is a saftey switch 86. The safety switch 86 is provided for the purpose of stopping the turbine pump 60 in the event the water level in either the mixing chamber 50 or in the space between the mixing chamber and the confining member 16 drops to a dangerously low level so that there is presented some danger of the pump running dry. The switch 86 may be any suitable type of switch which is actuated by the dropping of the water level below a certain point in the mixing chamber, or in the space therearound. Switches suitable for accomplishing this function are well known in the art. At such time as the water levels drop to a dangerously low level, the switch 86 will be opened, thus shutting down the turbine pump 60 and preventing the pump from running dry and destroying hearings or seals as a result of such dry operation.

From the foregoing description of the invention, it will have become apparent that the novel mixing apparatus proposed permits particulate materials, such as soap flakes, soap powder or the like, to be intimately mixed with a liquid, such as water, due to the combined effect of the water cascading into the mixing chamber over the upper edge thereof and from all sides of the mixing chamber, and to the shearing action of the turbine pump. Fresh water with very little or, in most instances, no soap entrained therein is made available for use during the rinsing cycle of the apparatus, and the system may be operated fully automatically over extended periods of time and through repeated cycles. The difliculty heretofore encountered in automatic car washing systems in which soap is premixed with water, and involving a change of the pH of the water so that bacteria can grow in the mixture, and scum accumulate thereon, is avoided. Thus, destruction of pumps and plumbing associated with the system as a result of pH change, and development of corrosive by-products of bacterial growth are also avoided due to the fresh mixing of the soap and water at each time of use. Also as a result of the intimate and thorough mixing achieved by the present apparatus, a better lathering action is produced as the soap-water mixture is directed against vehicles.

Although certain preferred embodiments of the invention have been hereinbefore described in order to provide an example to those skilled in the art of how the invention may be practiced, it is to be understood that various changes and modifications to the described structure can be efiected Without departure from the basic principles of the invention. All changes and modifications of this type are deemed to be circumscribed by the spirit and scope of the present invention except as the same may be necessarily limited by the appended claims or reasonable equivalents thereof.

What is claimed is:

1. In an apparatus for periodically and in sequence dispensing a plurality of fluent materials and including a common pump through which such dispensation occurs, the improvement comprising:

a housing for containing a first material;

an open-topped mixing chamber positioned below said housing 9. receiving material from said housing;

a liquid confining member outside said mixing chamber and defining a space therewith for containing a liquid in juxtaposition to the open top of said mixing chamber;

means for directing a liquid into the space between the confining member and the mixing chamber;

first conduit means connecting said mixing chamber to said pump;

second conduit means connecting to said pump, the space between the confining member and the mixing chamber; and

programming means for controlling liquid flow through said first and second conduit means to sequentially pump liquid from said mixing chamber and irom said space.

2. The improvement defined in claim 1 and further characterized to include control means connected to said liquid directing means and responsive to the liquid levels in said mixing chamber and in said space to control said liquid directing means to maintain said liquid levels within predetermined limits.

3. The improvement defined in claim 1 wherein said liquid confining member and said space surround said mixing chamber.

4. The improvement defined in claim 1 wherein said programming means includes:

a three-way solenoid valve connected to, and constantly communicating with, said pump;

a programmer connected to said three way valve for periodically shifting said three way valve to connect said pump in sequence to said first conduit means, then to said second conduit means.

5. The improvement defined in claim 1 wherein said second conduit means includes a liquid flow passageway extending from said space at a point between the lower ends of said mixing chamber and confining member, and wherein said means for directing a liquid into the space between the confining member and the mixing chamber comprises:

a fitting connected to a median portion of said liquid flow passageway; and

a conduit connected to said fitting; and

a source of liquid connected to said conduit.

6. The improvement defined in claim 1 wherein said mixing chamber and confining member are each of inverted conical configuration and are concentrically disposed with respect to each other.

7. The improvement defined in claim 1 and further characterized to include a feeding mechanism mounted on said housing for positively feeding said first material to said open-topped mixing chamber therefrom.

'8. The improvement defined in claim 2 wherein said control means comprises:

a first float element in said mixing chamber;

a second float element in said space;

parallel connected electrical float switches connected to said first and second float elements and opened and closed thereby as the liquid levels in said chamber and space rise and fall; and

a solenoid valve connected to each of said float switches and positioned to alternately pass and obstruct liquid directed by said liquid directing means.

9. The improvement defined in claim 4 wherein said programming means further includes means for starting and stopping said pump, and control means for controlling the flow of said first material from said housing to said mixing chamber to synchronize said flow of first material with the time at which said pump is connected through said three way solenoid valve to said first conduit means.

10. The improvement defined in claim 5 and further characterized to include valve means interposed in said conduit for controlling the flow of liquid therethr-ough from said source; and

valve actuating means connected to said valve means and responsive to the levels of liquid in said chamber and said space for opening said valve means when either of said liquid levels drops a predetermined amount.

11. The improvement defined in claim 6 wherein said housing is of inverted conical configuration and further characterized to include feeding mechanism mounted on said housing for positively feeding said first material to said open-topped mixing chamber therefrom, said feeding mechanism comprising:

a motor mounted adjacent the top of said inverted conical housing;

a drive shaft drivingly connected to said motor and extending downwardly and concentrically in said housing;

radial vanes secured to the lower end of the drive shaft;

and

a feeder housing surrounding said vanes and having a material inlet aperture and a material outlet aperture therein.

12. The improvement defined in claim 7 wherein said feeding mechanism is oepratively connected to said programming means and is operated thereby in synchronism with the pumping of liquid from said mixing chamber.

13. The improvement defined in claim 10 wherein said valve actuating means comprises a first float element in said mixing chamber;

a second float element in said space; and

a pair of float switches connected to said first and second float elements and in parallel to each other, and further connected to said valve means.

14. The improvement defined in claim 5 and further characterized to include a three-way solenoid valve connected to said pump, said liquid flow passageway, and to said first conduit means for alternately receiving liquid from said first conduit means and said liquid flow passageway and directing it to said pump.

References Cited UNITED STATES PATENTS 2,636,501 4/1953 Hilliker 222-57 X 3,140,049 7/1964 Norstrud et al 22257 X ROBERT B. REEVES, Primary Examiner. HADD S. LANE, Assistant Examiner. 

